Vertical take-off and landing aircraft

ABSTRACT

A VTOL aircraft is powered on regular fixed wing flight by a pair of jet engines on the after quarter of the fuselage and achieves vertical take-off and landing under the power of an articulated tail rotor which is retractable into a storage compartment of the fuselage during conversion from rotor flight to fixed wing flight. The take-off and landing rotor derives power for its blade tip jet nozzles through internal ducting which receives jet engine exhaust gas through a diversion system connected in the main jet exhaust nozzle of each engine. By-pass air is also diverted from each engine to the interior of the rotor blades and is further directed to rotor blade jet flap slots for maintaining rotor cyclic and collective pitch control without the customary complex mechanisms. Rotor directional control is maintained by diverting additional by-pass air to certain fixed wing jet flap slots. A mechanical traction device is utilized to retract and extend the rotor.

Pender Oct. 2, 1973 VERTICAL TAKE-OFF AND LANDING AIRCRAFT [76] Inventor: David R. Pender, 1018 Marion St.,

Columbia, 8.0 29201 22 Filed: Dec. 29, 1971 [21] Appl. No.: 213,245

[52] U.S. Cl. 244/7 A, 244/17.19

[51] Int. Cl. B64c 27/22 [58] Field of Search 244/7 A, 2, 6, 17.19, 244/13, 58, 139, 140

[56] References Cited UNITED STATES PATENTS 3,582,021 6/1971 Pander 244/7 A 2,629,570 2/1953 Carnahan... 244/7 R 3,119,577 1/1964 Andrews 244/7 R 3,185,408 5/1965 Higgins 244/7 R Priniary Examiner-Milton Buchler Assistant Examiner-Carl A. Rutledge At!0rneyB. P. Fishburne, Jr.

nnoaoonnonannnnnnmnnn g QtE-M 2 [57] ABSTRACT A VTOL aircraft is powered on regular fixed wing flight by a pair ofjet engines on the after quarter of the fuselage and achieves vertical take-off and landing under the power of an articulated tail rotor which is retractable into a storage compartment of the fuselage during conversion from rotor flight to fixed wing flight. The take-off and landing rotor dlerives power for its blade tip jet nozzles through internal ducting which receives jet engine exhaust gas through a diversion system connected in the main jet exhaust nozzle of each engine. By-pass air is also diverted from each engine to the interior of the rotor blades and is further directed to rotor blade jet flap slots for maintaining rotor cyclic and collective pitch control without the customary complex mechanisms. Rotor directional control is maintained by diverting additional by-pass air to cer tain fixed wing jet flap slots. A mechanical traction device is utilized to retract and extend the rotor.

31 Claims, 41 Drawing Figures PAIENTEDBEI 2191a" SHEET 010F18 INVENTOR DQVVJ Fend B- P 9%, ATTORNEY PATENTED 2'975 3.762.667

SHIET 02 0F 18 PATENTEBUBI 2 ms saw on or 1a PAIENTEUum 2 ma sum osor 1a PAIENTEUBBT e m sum as or 18 PATENIEI] UET 21975 SHEET .0? 0f 18 PATENTEI] 21 75 sum 06 or 16 PAIENI nnm 2mm sum 10 or 18 PATENTED 3.782.667

SHEET 11 0F 18 Ill. 3

PATENTED 2 I975 SHEET 12 0F 18 PAIENTED w 2 I913 SHEET 1% 0F 18 FIG. l3

FIG. l4

PATENTED BET 2 I973 sum 1sur'1a PATENTED 2 75 MEI 110F10 FIG. 23

FIG. 24

FIG.

FIG. 26

VERTICAL TAKE-OFF ANI) LANDING AIRCRAFT BACKGROUND OF THE INVENTION The present invention is an improvement upon the basic vertical take-off and landing aircraft disclosed in US. Pat. NO. 3,582,021 issued to David R. Pender on June 1, 1971. In that patent, an aircraft and method of operation is disclosed and claimed wherein a fixed wing airplane, such a passenger airliner, is lifted vertically by the tail through the action of a powered tail rotor at take-off. The aircraft is then converted to standard fixed wing flight by collapsing of the tail rotor blades and retraction of the rotor into a longitudinal storage space in the fuselage. The rotor is deployed in a reverse manner for converting once again to rotor flight to effect landing of the aircraft in a vertical attitude nose downward.

The object of the present invention is to provide practical and reasonably economic means for diverting power from the aircraft jet engines to the tail rotor to produce and maintain powered rotation thereof and to accomplish rotor directional control and collective and cyclic pitch control of the rotor blades without the necessity for the complex mechanisms customarily embodied in helicopters.

In accordance with the invention, a passenger airliner of generally conventional configuration has a pair of fan jet engines or the like podded on opposite sides of the fuselage aft of the fixed wings. Valved ducting is connected into the main exhaust nozzle of each engine for diverting hot exhaust gas and cool by-pass air, either mixed or separately, from each engine into a pair of common ducts which extend aft at the center of the fuselage. The duct delivering hot exhaust gas from the aircraft engines to jet nozzles on the tips of the two bladed tail rotor communicates through a sliding seal with a movable exhaust gas duct which ultimately delivers hot exhaust gas through branch flexible conduits to internal passages of the rotor blades and through these passages to the blade tip jet nozzles. Simultaneously, the common duct for by-pass air leading from the two engines is divided into two branches and further sub divided into four separate passageswhich communicate cyclically and variably with quadrant passages in the rotor mast which has stationary and rotating interfaces. In this manner, the required cyclic and collective pitch control of rotor blades can be obtained without resort to awkward and complex mechanical linkages. The lay-pass air diverted and delivered to the interior of the two rotor blades through the divided passage means is further directed to rotor blade jet flap slots where the resulting jet reaction produces the necessary control function on the blades and rotor, as will be fully described. Further diversionary means inthe by-pass air duct system is provided to deliver by-pass air to certain fixed wing tip jet flap slots for rotor directional control, and also jet elevator slots and fixed wing jet flaps. As will be described, there elements are utilized to effectively control the craft during flight on the tail rotor and during regular fixed wing flight and during conversion to and from rotor and fixed wing flight.

A mechanical traction system is provided in the rotor storage compartment of the fuselage to retract and to begin the deployment of the articulated rotor at proper times. This means functions in conjunction with guide rollers and trackage of the rotor stowage compartment and hinged rear rotor stowage door to assure efficient deployment and retraction of the rotor.

The aircraft contains numerous additional features and advantages, including important safety features, which will be described in the detailed description, to follow. One such important feature is an arrangement whereby the tail rotor may continue to operate satisfactorily should one engine of the aircraft fail. Another important aspect of the invention to be described in detail resides in the gradual conversion or transi-tion from relatively large circular cross section jet engine exhaust gas and air passages to relatively low profile side-byside gas and air ducts. This feature minimizes air drag at critical points on the craft and greatly simplifies the gas and air diverting valve means and controls.

Other detailed features and advantages of the invention will become apparent during the course of the following detailed description.

BRIEF DESCRIPTION OF DRAWING FIGURES FIG. 1 is a side elevation of an aircraft embodying the invention at rest on the ground.

FIG. 2 is a rear end elevation of the aircraft with the lifting rotor retracted, the rotor being shown in broken lines in a deployed rotor flight position.

FIG. 3a is a fragmentary bottom plan view of the aircraft with the rotor retracted, the rotor outline in a flight position being shown in broken lines.

FIG. 3b is a fragmentary top plan view of the aircraft similar to FIG. 30.

FIG. 4 is a side elevational view, partly broken away, illustrating the process of converting from rotor flight to fixed wing flight.

FIG. 5 is a side elevation, partly broken away, showing the aircraft on fixed wing flight with the rotor retracted.

FIG. 6 is a fragmentary horizontal cross section of one engine of the aircraft and the associated ducts and diverter valves leading to the rotor.

FIGS. 7a and 7b together constitute a top partly diagrammatic plan view, partly in section, of the rear of the aircraft showing the duct work and valving from the jet engines, parts omitted for clarity.

FIG. 8a is a side elevation, partly in section, of the rear portion of the aircraft showing components of the rotor in the on ground" position.

FIG. 8b is an enlarged fragmentary cross sectional view through the rotor structure in the same position depicted in FIG. 8a, parts in elevation;

FIG. is an enlarged fragmentary cross section, partly in elevation, through ducting and other components in the rear of the aircraft associated with the rotor arid being shown on a smaller scale in elevation in FIG. 8a.

FIGS. and 9b together constitute a top plan view of the rotor structure which slides into and out of the rear end of the aircraft. The rotor blades in this figure are seen to be in the open or unfolded flying position at right angles to the rotor mast.

FIGS. 10a and 10b together constitute a longitudinal cross section, partly in elevation, through one rotor blade and hub with the rotor blade in the open or unfolded position.

FIG. lla is a fragmentary vertical cross section through the aircraft near the rotor storage door and tail plane. 

1. A vertical take-off and landing aircraft comprising a fixed wing aircraft body portion having a pair of jet propulsion engines and a rear opening longitudinal fuselage rotor stowage compartment, a take-off and landing rotor for the aircraft adapted when deployed outside of said stowage compartment to lift the aircraft tail upwardly with the nose of the craft downwardly, a carriage means for said rotor having tracked engagement with said stowage compartment, power traction means connected with said carriage means to move the carriage means in opposite directions in the stowage compartment for retracting and deploying the rotor, said rotor comprising a mast including rotating and non-rotating parts, means forming a universal type mechanical connection between the carriage means and non-rotating part of the mast, a pair of lifting rotor blades having jet nozzle means at their tips and jet flap slots near longitudinal edges thereof, mechanical linkage means pivotally connecting said blades to the rotating part of said mast in such a manner that the blades may fold upwardly into substantial parallelism to facilitate retraction thereof into said stowage compartment, valved conduit means for diverting exhaust gas from said jet engines and delivering the same through said mast and rotor blades to said tip jet nozzle means to produce rotation of said blades, and additional valved conduit means for diverting by-pass air from said jet engines and delivering it cyclically and variably through said mast and blades to said jet flap slots, said valved conduit means for diverting exhaust gas comprising a duct connected in the exhaust jet nozzle of each engine and leading to and joined with a common center exhaust gas duct in the after portion of the aircraft fuselage, a coacting common exhaust gas duct on the carriage means and movable therewith, and means forming a sliding seal between opposing ends of said common ducts whereby exhaust gas may pass from one into the other without leakage when the common ducts are in registry.
 2. The structure of claim 1, and a flexible duct section for exhaust gas interconnecting said non-rotating rotor mast part and said common exhaust gas duct of the carriage means.
 3. The structure of claim 1, and said aircraft body portion having a floor partition and rear facing passenger seats in the fuselage above the rotor stowage compartment.
 4. The structure of claim 3, and a cockpit in the nose portion of the fuselage including seats and aircraft controls for a first pilot who pilots the aircraft during normal fixed wing flight and for a second pilot who pilots the aircraft during rotor flight while the fuselage is substantially vertical and nose down.
 5. The structure of claim 4, and a shock-absorbing nose structure on the fuselage to facilitate landing the aircraft nose downwardly into contact with the ground.
 6. The structure of claim 4, and said cockpit having windows for the two pilots on the top and bottom of the aircraft nose, the seat for the rotor flight pilot facing downwardly and rearwardly adjacent the windows on the bottom of the nose.
 7. The structure of claim 1, and a door hingedly secured to the rear of the fuselage and serving in one position to cover the rear open end of said rotor stowage compartment and serving in a second position as a ground support for the aft end of the fuselage, and guidance means for folded rotor blades on said door operable in the open position of the door to assist in guiding the rotor into the stowage compartment.
 8. The structure of claim 7, and a shock-absorbing means on the rotor stowage door adapted to contact the ground at the completion of landing of the aircraft.
 9. The structure of claim 5, and means to guide and lock into place in an uPright position the mast structure of said rotor on landing of the aircraft when the fuselage thereof moves to a substantially horizontal position and the rotor is stopped.
 10. The structure of claim 7, and a power actuator for said door mounted in said fuselage.
 11. The structure of claim 1, and means to automatically rotate the rotor on its axis with the rotor blades folded so as to properly align the folded blades for proper entry lengthwise into said stowage compartment.
 12. The structure of claim 1, and a center located fixed target thrust spoiler near the aft portion of the fuselage, and a coacting power-operated thrust reverser door adjacent the thrust spoiler, whereby the exhaust gas from both aircraft engines may be directed to the thrust spoiler.
 13. The structure of claim 12, and said thrust spoiler being tiltable to assist in maneuvering the aircraft out of a dive at low speed for rapid conversion from rotor flight to fixed wing flight.
 14. The structure of claim 1, and linkage means interconnecting the rotating part of said mast and said blades to stabilize the blades and to control and limit flapping thereof, said linkage means including a pair of fluid pressure activated cylinder units which control and dampen the flapping action of said blades.
 15. The structure of claim 1, and each lifting rotor blade having an internal exhaust gas distribution system directing exhaust gas to said blade tip jet nozzle means, and each blade having an internal chamber and guidance means directing by-pass air to said blade jet flap slots.
 16. A vertical take-off and landing aircraft comprising a fixed wing aircraft body portion having a pair of jet propulsion engines and a rear opening longitudinal fuselage rotor stowage compartment, a take-off and landing rotor for the aircraft adapted when deployed outside of said stowage compartment to lift the aircraft tail upwardly with its nose downwardly, a carriage means for said rotor having tracked engagement with said stowage compartment, power traction means connected with said carriage means to move the carriage means in opposite directions in the stowage compartment for retracting and deploying the rotor, said rotor comprising a mast including rotating and non-rotating parts, means forming a universal type mechanical connection between the carriage means and non-rotating part of the mast, a pair of lifting rotor blades having jet nozzle means at their tips and jet flap slots near longitudinal edges thereof, mechanical linkage means pivotally connecting said blades to the rotating part of said mast in such a manner that the blades may fold upwardly into substantial parallelism to facilitate retraction thereof into said stowage compartment, valved conduit means for diverting exhaust gas from said jet engines and delivering the same through said mast and rotor blades to said tip jet nozzle means to produce rotation of said blades, additional valved conduit means for diverting by-pass air from said jet engines and delivering it cyclically and variably through said mast and blades to said jet flap slots, said additional valved conduit means diverting by-pass air from said jet engines comprising a by-pass air duct connected in the by-pass air channel of each jet engine and leading to and connected in a common by-pass air duct in the after portion of the fuselage and near the center thereof, said common by-pass air duct being divided into two valved branches and said two branches being sub-divided into four duct branches, a like number of by-pass air duct branches on the carriage means and movable therewith, and means forming a sliding seal between the opposed mouths of said four duct branches on the fuselage and coacting branches on the carriage means.
 17. The structure of claim 16, and plural flexible duct sections for by-pass air interconnecting said duct branches on the carriage means with variable by-pass air passages of the rotor mast.
 18. The structure of claim 17, and additional flexible duct sections cOnnected with the rotating part of the mast and the interior of said rotor blades and placing the jet flap slots of the rotor blades in communication with said variable passages of the rotor mast.
 19. The structure of claim 18, and said variable by-pass air passages of the rotor mast including relatively stationary quadrant passages in the non-rotating part of said mast,and a pair of divided by-pass air passages in the rotating part of the mast and being circumferentially coextensive with the non-rotating quadrant passages and movable relative thereto circumferentially to cylically vary the movement of by-pass air to said rotor blade jet flap slots.
 20. A vertical take-off and landing aircraft comprising a fixed wing aircraft body portion having a pair of jet propulsion engines on opposite sides of the aircraft fuselage, said fuselage having a longitudinal rear opening rotor stowage compartment, a lifting rotor for the aircraft adapted to be deployed through the rear of the stowage compartment and raising and lowering the aircraft in a nose down vertical attitude for take-off and landing, mechanical power means connected with the rotor to retract the same into the stowage compartment and to move the rotor rearwardly therefrom, said rotor including a pair of hinged foldable airfoil blades having jet nozzles thereon to produce rotation of the rotor and having jet flap slots by means of which the pitch of the blades and the directional attitude of the rotor may be regulated, fixed conduit means on the aircraft body portion connected with said jet propulsion engines for diverting exhaust gas and by-pass air therefrom for delivery to the rotor, coacting conduit means movable with the rotor into selaed registration with the fixed conduit means when the rotor is deployed, and passage means on the rotor and within the blades thereof for delivering engine exhaust gas to said blade jet nozzles and for cyclically and variably delivering by-pass air from the engines to said blade jet flap slots.
 21. The structure of claim 20, and adjustable valving means in the fixed conduit means for regulating the volumetric flow of exhaust gas and by-pass air diverted from said engines to the rotor.
 22. The structure of claim 20, and a mast structure for said lifting rotor including rotating and non-rotating interfitting components, said components having divided exhaust gas passage means and divided relatively movable variable passage means for by-pass air, and said last-named exhaust gas and by-pass air passage means of the mast structure communicating with said coacting movable conduit means.
 23. A vertical take-off and landing aircraft comprising a fixed wing aircraft body portion having a pair of jet propulsion engines and a rear opening longitudinal fuselage rotor stowage compartment, a take-off and landing rotor for the aircraft adapted when deployed outside of said stowage compartment to lift the aircraft tail upwardly with the nose of the craft downwardly, a carriage means for said rotor having tracked engagement with said stowage compartment, power traction means connected with said carriage means to move the carriage means in opposite directions in the stowage compartment for retracting and deploying the rotor, said rotor comprising a mast including rotating and non-rotating parts, means forming a universal type mechanical connection between the carriage means and non-rotating part of the mast, a pair of lifting rotor blades having jet nozzle means at their tips and jet flap slots near longitudinal edges thereof, mechanical linkage means pivotally connecting said blades to the rotating part of said mast in such a manner that the blades may fold upwardly into substantial parallelism to facilitate retraction thereof into said stowage compartment, valved conduit means for diverting exhaust gas from said jet engines and delivering the same through said mast and rotor blades to said tip jet nozzle means to produce rotation of said blades, additional valved conduit means for diverTing by-pass air from said jet engines and delivering it cyclically and variably through said mast and blades to said jet flap slots, and additional by-pass air duct means for delivering by-pass air to fixed wing jet flaps and elevator jet flaps on the aircraft.
 24. A vertical take-off and landing aircraft comprising a fixed wing aircraft body portion having a pair of jet propulsion engines and a rear opening longitudinal fuselage rotor stowage compartment, a take-off and landing rotor for the aircraft adapted when deployed outside of said stowage compartment to lift the aircraft tail upwardly with the nose of the craft downwardly, a carriage means for said rotor having tracked engagement with said stowage compartment, power traction means connected with said carriage means to move the carriage means in opposite directions in the stowage compartment for retracting and deploying the rotor, said rotor comprising a mast including rotating and non-rotating parts, means forming a universal type mechanical connection between the carriage means and non-rotating part of the mast, a pair of lifting rotor blades having jet nozzle means at their tips and jet flap slots near longitudinal edges thereof, mechanical linkage means pivotally connecting said blades to the rotating part of said mast in such a manner that the blades may fold upwardly into substantial parallelism to facilitate retraction thereof into said stowage compartment, valved conduit means for diverting exhaust gas from said jet engines and delivering the same through said mast and rotor blades to said tip jet nozzle means to produce rotation of said blades, additional valved conduit means for diverting by-pass air from said jet engines and delivering it cyclically and variably through said mast and blades to said jet flap slots, and automatic valve means in said valved conduit means for diverting exhaust gas and in said additional valved conduit means for diverting by-pass air and being automatically operable in response to failure of either aircraft engine to assure a continued adequate flow of exhaust gas and by-pass air to said rotor.
 25. The structure of claim 24, and said automatic valve means consisting of a pair of independently pivoted flip-flop valve plate elements in said conduit means and additional conduit means and being automatically self-centering in the presence of exhaust gas and by-pass air streams from both of said engines.
 26. A vertical take-off and landing aircraft having a tail lifting take-off and landing rotor and fixed wing means for normal flight, a pair of laterally spaced jet engines on the aircraft including exhaust gas and by-pass air passage means, said rotor having a pair of airfoil blades containing jet flap slots for regulating blade pitch and also having blade tip jet nozzles for producing rotation of the rotor, and a jet flap cyclic control system for the rotor which includes a bifurcated duct for by-pass air diverted from the by-pass air passage means of said engines, a valve immediately upstream from said bifurcated duct enabling by-pass air to be directed into either branch of the bifurcated duct, another valve arranged in each branch of the bifurcated duct and having common control means, an additional pair of sub-branch ducts leading from each said branch of the bifurcated duct, said sub-branches being downstream from said valves in said branches having the common control means, whereby the volume of by-pass air to any of the sub-branch ducts can be varied, a rotor mast structure intervened between said sub-branch ducts and blade jet flap slots and containing a circumferential passage for by-pass air divided into four quadrants which are non-rotating, said mast structure having a mating interfitting circumferential passage for by-pass air which is divided into a pair of semi-circular segments and which rotates, said quadrants and semi-circular segments communicating to achieve cyclic variation in the volume of by-pass air being delivered to the blade jet flap slots, anotHer pair of ducts interconnecting said semi-circular segments with an interior chamber of each rotor blade leading to the jet flap slot of the blade, and valved conduit means between the aircraft engines and interior passage means of said blades for delivering engine exhaust gas to said blade tip jet nozzles.
 27. The structure of claim 26, and said valved conduit means for delivering said exhaust gas including a passage for exhaust gas in the rotating part of the mast structure and inwardly of said quadrants, said passage being internally divided into two sections each delivering exhaust gas to the tip jet nozzle of one rotor blade.
 28. The structure of claim 26, and a blade root arm for each rotor blade, a pair of hinge supports for said root arms to allow upward folding of the blades and varying of the blade coning angle, said hinge supports carried by the rotating part of the rotor mast structure, means forming a single teetering hinge above said hinge supports, blade fold-up slide pole means extending above the teetering hinge, slide units movably mounted on the slide pole means, and a pair of widely spaced blade support arms connected to each blade near the leading and trailing edges thereof, said arms also connected with said slide units.
 29. The structure of claim 26, and each of said airfoil blades of the rotor comprising a hollow blade body, an insulated unitary exhaust gas duct system slidable as a unit into the blade body, a bolt-on blade tip cascade nozzle structure for the blade body communicating with said duct system, and a bolt-on blade root end plate for the blade body serving to anchor said duct system and adding structural integrity and rigidity to the blade.
 30. The structure of claim 29, and a slip-type expansion joint between said dut system and blade tip cascade nozzle structure.
 31. The structure of claim 26, and said first and second named valves comprising butterfly-type valves having off-center pivots and being self-centering in the slipstream in which they are disposed in the absence of a positive controlling force thereon. 